package com.zhao.apitest.transform;

import com.zhao.apitest.beans.SensorReading;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.java.tuple.Tuple;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;

/**
 * @author ZhaoPan
 * @date 2022/3/11
 * @describe
 */
public class TransformTest2_RollingAggregation {
    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        env.setParallelism(1);

        //从文件读取数据
        DataStream<String> inputStream = env.readTextFile("E:\\flinkTest\\src\\main\\resources\\sensor.txt");

        // 转换成SensorReading类型
        DataStream<SensorReading> dataStream=inputStream.map(new MapFunction<String, SensorReading>() {
            @Override
            public SensorReading map(String s) throws Exception {
                String[] fields=s.split(",");
                return new SensorReading(fields[0],new Long(fields[1]),new Double(fields[2]));
            }
        });

        // DataStream<SensorReading> dataStream = inputStream.map(line -> {
        //     String[] fields = line.split(",");
        //     return new SensorReading(fields[0], new Long(fields[1]), new Double(fields[2]));
        // });

        // 分组
        KeyedStream<SensorReading, Tuple> keyedStream = dataStream.keyBy("id");
        // KeyedStream<SensorReading, String> keyedStream1 = dataStream.keyBy(SensorReading::getId);

        //滚动聚合,取当前最大的温度值
        // DataStream<SensorReading> resultStream = keyedStream.maxBy("temperature");
        DataStream<SensorReading> resultStream = keyedStream.maxBy("temperature");

        resultStream.print();

        env.execute();
    }
}
